Stellarium ~ Carte Du Ciel discrepancy

chrisp9au (Chris) · #1 15-02-2013, 01:29 PM

Now this has got me interested/worried.
What worries me most is that I'm about to make an absolute fool of myself!

For the occultation of Jupiter by the Moon on Monday February 18th,
Stellarium 0.12.0 and Carte Du Ciel 3.6-2150 are showing completely different occultation times.

Both Stellarium and CDC show Sunset to be at 20:14 local time, no worries.
Both are setup for my location, accurate to the arc second.

Moving forward from Sunset to 21:08 local time...

Stellarium shows, Pic 1, the occultation of Jupiter commencing at 21:08:46
CDC, at the exact same time, shows, Pic 2, a wide separation.

Moving forward in CDC to 23:32 local time...
Pic 3 shows the CDC display with the occultation commencing.

Now, I suspect there is something screwy with Stellarium,
but whether it's my settings or the Stellarium ephemeris I don't know?
As far as I can tell, my settings are exactly the same in both programs.

Can anyone explain the 2 1/2 hour discrepancy?

Can anyone replicate this?

Thanks

Chris

PS If I've done or said anything stupid, please be gentle in your response! Thank you!

bojan · #2 15-02-2013, 02:22 PM

CdC v2.76c shows the same as V3.

In the past, CdC (2.76c) was accurate and reliable.
I had some similar issues with Stellarium, that is why I am still using CdC v2.76c (I am accustomed to older version.. so why change if it works OK).

Steffen · #3 15-02-2013, 02:54 PM

FWIW, SkySafari Pro 1.7.3 seems to agree with CdC, it puts the occultation (centre of Jupiter) at 23:32:43h for Melbourne.

Cheers
Steffen.

chrisp9au (Chris) · #4 15-02-2013, 02:55 PM

Thanks Bojan,

Yes, CDC is reliable although the display in the later versions seems a clunky these days, takes for ever to update when you slew the display. Mouse control is a waste of time too.

I checked SkySafari Plus on my Nexus 7 for the occultation; confirmed the time of 23:32.

It would appear to be a problem with the Stellarium ephemeris data for Jupiter.

Cheers

Chris

chrisp9au (Chris) · #5 15-02-2013, 02:56 PM

Thanks Steffen!

chrisp9au (Chris) · #6 15-02-2013, 03:40 PM

OK, I un-installed Stellarium, removing all traces of it.
Have now loaded version 11.4 and the occultation timing is correct.

Maybe it's a problem with version 12, I'll stick to this old version for now.

Cheers

Chris

Barrykgerdes · #7 15-02-2013, 04:27 PM

Hi Chris

I think there was a bug in the first release of 0.12.0. There have been over 100 changes since then

My 0.12.1 version does not have an occulation at all for Sydney. But When I set Melbourne the oculation starts at about 23:31

You can find a later version here:

https://launchpad.net/stellarium/+download

Barry